EngineSimulationClock.cs

namespace Gondwana.Timers;

internal static class EngineSimulationClock
{
    private static long _simulationTick = HighResTimer.GetCurrentTick();
    private static int _timerDriven;

    internal static long GetCurrentTick() => Volatile.Read(ref _timerDriven) != 0
        ? Interlocked.Read(ref _simulationTick)
        : HighResTimer.GetCurrentTick();

    internal static void BeginTimerDriven(long tick)
    {
        Interlocked.Exchange(ref _simulationTick, tick);
        Volatile.Write(ref _timerDriven, 1);
    }

    internal static void SetTimerDrivenTick(long tick) =>
        Interlocked.Exchange(ref _simulationTick, tick);

    internal static void UseWallClock() => Volatile.Write(ref _timerDriven, 0);
}